Import the file you exported from LINE with "Send chat history" into 24h. Only you can see it.
4 steps · about 1 min
Steps
1
In a LINE chat, open the menu at the top right and choose "Send chat history". This creates a .txt file.
Screenshot comingLINE chat, menu at the top right with "Send chat history" highlighted
2
Choose "Share" and send the file to 24h (or save it to your phone first).
Screenshot comingShare sheet with 24h highlighted
3
In 24h, tap "Import chat memories", or go to Me › General › Import chat memories and pick the file.
Screenshot comingMe › General › Import chat memories, with the file picker button highlighted
4
Check the chat name and message count. Only the last 30 days are imported by default. You can pick your own name so your messages appear on the right, then tap "Import".
Screenshot comingPreview before importing, with the days option and "Who are you in this chat" highlighted
Once imported, only you can see it. It doesn't appear in any chat, is never sent to AI, and can't be shared.
Photos, stickers and videos only show up as text.
Imported chat memories count toward your storage.
To delete, open the chat and tap the trash can at the top right to delete the whole thing.
The chat contains other people's messages, so please use it only to keep your own memories.